I don't use acetone on the windows but have not observed any visible harm for use on gelcoat. More harmful to lungs & tissue.

Next time, I may try what I've seen on Yeti, a foam automotive like weather seal. Also, if you are in a jam, blue tape the window edges before a race or use Stay Afloat puddy (smells like jerky) if surface is dry or wet. Jam into joints or cracks.

JB

:: Tell us more about NOT using acetone or solvents. What
:: should be used and why no acetone or solvents. SDK
::
::
::
:: :: No posted instructions that I know of, though you can
:: :: search the internet and find various approaches people
:: :: have taken.
:: ::
:: :: Generally windows leak through the screw holes, though
:: :: if not well sealed originally they can leak anywhere.
:: :: The cabin top flexes a lot when walked on and will break
:: :: the seal for the windows. If the windows are in very
:: :: good shape and seem well sealed you can try removing
:: :: offending screws, sealing them with silicone, and
:: :: replacing them.
:: ::
:: :: To re-bed the windows they must be removed, all old
:: :: sealant carefully cleaned from boat and windows
:: :: (difficult as you should avoid using acetone or solvents
:: :: to clean the boat or windows), and then resealed. It may
:: :: be a good time to replace them--if you take the old
:: :: windows to Tap Plastics they will fabricate new windows
:: :: for a very reasonable price. Have them drill the screw
:: :: holes also (oversize to allow for expansion), as
:: :: drilling through lexan without a proper drill will cause
:: :: micro cracks that spread later. Note that Tap will bevel
:: :: and/or melt edges to your specifications for a very nice
:: :: look.
:: ::
:: :: After breaking several windows during races, I switched
:: :: to polycarbonate windows, which scratch more easily but
:: :: are much much stronger.
:: ::
:: :: When re-bedding windows, you want to have a good
:: :: thickness of silicone. One trick I learned for this is
:: :: to cut tiny squares of white electrical tape and placing
:: :: them near (1/4" away from) the screw holes, so when you
:: :: fasten the window in place there is still a thickness of
:: :: silicone to make the seal. Don't tighten the screws
:: :: until the silicone has set up somewhat, and then don't
:: :: tighten them very much. Remember, you want a thickness
:: :: of silicone to make the seal.
:: ::
:: :: Masking over everywhere that silicone should not go
:: :: (window, cabin top) is a good idea, as silicone that
:: :: gets loose will both make a mess and make future
:: :: painting / repair jobs go poorly.
:: ::
:: :: I have an Express 37 with the original windows (very
:: :: hazy but no leaks). They have very thick silicone layer
:: :: (perhaps 1/8" thick). I'm not sure what trick they used,
:: :: but it has been very effective over the years.
:: ::
:: ::
:: ::
:: ::
:: ::
:: :: :: Where can I find how to repair Express Window water
:: :: :: leak?
:: ::
:: :: :: I heard it is common for Express 27. Any article or
:: :: :: instruction for the repair?